Heating apparatus



Patented June 25. 1946 HEATING APPARATUS Moritz L. Mueller, Seattl mesneassignments, to John H. Mueller, Seattle, Wash., as jointtenants e,Wash, assignor, by Moritz L. Mueller and Application March 23, 1942,Serial No. 435,813 11 Claims. (Cl. 237-2) This invention relates toheating apparatus and has particular relation to a new and improved typeof apparatus comprising a chimney furnace with provisions in the bottomthereof for independently burning a plurality of different kinds offuel.

A principal object of the invention is to provide a novel and improvedtype of heating system for supplying heated air to a space in a buildingto be occupied by and for the comfort of human being comprising achimney which forms a part of the building and which extends upright toand above the roof of the building and has an atmospheric dischargeexternal of the space, a combustion chamber in the lower portion of thechimney constructed and arranged for burning a plurality of ,difierentkinds of fuel'under natural draft operation, and a heat exchanger withinand extending along a substantial portion of the length of the chimneyand providing a means for efficiently transferring heat from thecombustion products to air which is delivered to the space to be heatedfor heating the same.

Another object of the invention is to provide a heating system'of thecharacter described with a combustion chamber which i constructed andarranged normally to burn one kind of fuel, said combustion chamberbeing provided with means for burning a different kind of fuel which maybe operated simultaneously with or independently of the normal fuelburning means.

Another object of the invention is to provide a heating system with acombustion chamber adapted to burn either'gas or oil fuel under naturaldraft operation together with means for burning hard fuel eitherindependently of or simultaneously with the operation of the gas or oilburning mean and which hard fuel burning means are adapted to functionas an incinerator for disposing of rubbish.

Other objects and advantages of the invention will be apparent .from aconsideration of the following specification taken in conjunction withthe accompanying drawings, of which thereare two sheets and wherein:

Figure lis a vertical cross section through a part of a houseillustrating one form of heating system embodyin the invention and themethod of circulating the air to be heated through the heating systemand through the house;

Fig. 2 is an enlarged elevational view of part of the heating systemillustrated in Fig. 1 with certain parts broken away;

Fig. 3 is an enlarged vertical sectional view through .the combustionchamber and the lower part of the heat exchanger of the systemillustrated in Fig. 2;

Fig. 4 is a sectional view with parts shown in elevation taken along thestaggered line 4- of Fig. 2, looking in the direction of the arrows;

Fig. 5 is a horizontal sectional view taken along the line 5-5 of Fig.4;

Fig. 6 is a horizontal sectional view taken along the line 66 of Fig. 3and illustrating certain details of the combustion chamber; and v V Fig.7 is a diagram of a control circuit for the air blower of the heatingsystem. a

As illustrated in the embodiment of the invention selected for purposesof illustration, a heating system embodying my invention comprises ingeneral and as illustrated in Figs. 1, 2 and 3, a chimney II) whichforms part of the building indicated generally at l2 and which extendsupright to and above the roof M of the building andhas an atmosphericdischarge IB external of the space l8 in the building i2 to be heated. Acombustion chamber indicated generally at 20 i formed in the lOWerportion of the chimney i0 and is constructed and arranged for burningfuel under natural draft operation. The chimney l0 may be ofconventional masonry construction and of rectangular cross section asillustrated, and is provided with a heat exchanger indicated generallyat 22, said heat exchanger being within and extending along asubstantial portion of the length of .the chimney l0 and providing apath 24 for the flow of the products of combustion and a separate path26 for the fiow of air in intimate heat exchange relationship with thepath for flow of the combustion products upwardly through saidcombustion products .path 24.

Means are provided outside of said chimney In to supply from the spacel8 to the upper portion of the air path 26 air to be heated under apressure greater than the pressure of the products of combustion, andsuch means comprise an air moving device or blower 28 arranged to bedriven by an electric motor 30, a conduit indicated generally at 32leading through the attic space 34 of the building, one end of theconduit being connected to the intake side of the blower 28'and theother end of the conduit 32 communicating with return air opening 36communicating with the space I 8 to be heated. The chimney I0. isprovided with one or. more outlet openings 38 leading from the lower endof the air path 26 and adapted for discharging heated air into the spacel8. g a

The combustion chamber ZO is arranged in the lower. part of the chimneyand is defined at least The combustion chamber part or portion 62 may asillustrated have operatively associated.

therewith a fluid fuel burning means. such as a pot orheat vaporizingtype of burner indicated generally at 46 to which oil from a reservoir(not shown) is supplied under the control of an oil control valve 48which may be provided with a' changer thereabove. The foot 68 isprovided with a laterally extending continuous flange 10 which isadapted to seat on and be supported b a suitable ledge formed internallyof the chimney Ill at the upper end of the combustion chamber 20. Theheat exchanger 22 separates the combustion chamber from the spacethereabove and surrounding the heat exchanger 22 and cooperates with thechimney to provide the path as for the products of combustion and thepath 25 for the air to be heated.

The upper end of the air path 25 is closed by a transverse plate 12through which the upper end manual control 50 by means of which therate.

of flow of oil to the burner 45 may be regulated.

The burner 45 comprises an atmospheric or heat vaporizing type of burnerand. includes a pot provided with suitable air openings thereinto forsupplying air to the burner and'the combustion chamber so :as to providea combustible mixture of fuel and air, and to support combustion. Thepot burner includes a plate 52 extending tran versely of the chamberportion 42 and supported by the walls thereof. The plate filhas anOpening therein above the pot so as to permit the combustion of the .oilvapors within the combustion chamber 42, The pot 46 maybe supported by.the plate 52 and an air intake opening 54 is provided in the wall of thechimney below the burner 45 for supplying air thereto. A suitable door56 maybeprovidedin the wall of the combustion chamber. for obtainingaccess theretcin order to light the burner 46 which may be accomplishedby throwing a lighted flare. into the pot d5 when there is oil therein.

The valve 48 may be set to .co' trol ,thesupply of oil to the burner 45so as to produce a .pilot flame or to produce a high flame or a flameintermediate the high flame (and the pilot flame, depending upon theposition of the control handle 50. The products of combustion.resultingfrom the operation of the burner 45' are supplied undernatural draft to the flue or combustion products path 24..

The combustion chamber 44 is constructed and arranged for burning a hardfuel such as coal or wood and i also adaptedforfunctioningas anincinerator to burn ,combustiblerubbish. ,)To this end the chamber-4 5is provided with rates 5 3 for supporting the fuel-to be burned Accessto the chamber 44 is provided by .afliel door. 66 car.-

ried by a metallic Wall 62 whichjclosesone side of the chamber 44. Thewall 62 may also -be provided with'anash removal door '55 having .adamper controlled air inlet opening .55 foradmitting air to thecombustion chamber below the grates 58 forsupporting combustion in thechamber 44. 1

If desired the walls of the chimney iii which define the combustionchambers and 44 each of which'forms a .part of the combustion chamber 20may be formedof insulating brick so as' to reduce the heat transfer.through the walls thereof.

The heat exchanger 22 comprises as illustrated an elongated tubularmember or p pecomposed of 'aseries of lengths of stove pipe arranged inend to end relationship and a foot 68, thewal ls of which foot 66 may beformed or metal of substantially. greater thickness than the .walls ofthe lengths of pipeused to provide the heat exof the heat exchanger 22extends and which plate i2 functions to separate the flue path 24thereabove from the air path 25. The foot 58 supports the pipe sectionswhich comprise the heat exchanger 22 and in turn is supported by theside walls of the chimney Hi. The blower 28 may be mounted on a plate'54 secured to the upper portion of the chimney H! and have itsdischarge 16 arranged to deliver air through an openin 18 formed in thechimney wall l0 and adjacent the upper end of the heat exchanger 22 andbelow the plate 12. As the air discharged by the blower 28 into the airpath or duct 26 is under a pressure greater than the pressure of theproducts of combustion in the path or duct 2%, any leakage of the heatexchanger 22 will not contaminate the air path but will merely permitleakage of air into the flue 24,

The motor 30 which drives the blower 28 may be arranged in a circuitcontrolled by a thermostatic switch 82, said thermostatic switch 82being mounted on the chimney Wall and. having the thermal element 84thereof arranged in the flue 24 immediately above the upper end of theexchanger 22 so as to be responsive to the temperature of the productsof combustion as the same leave the heat exchanger 22. The switch 82 maybe set to close the motor circuit when the flue gas temperature reachesa certain'degree, say, for example, 225 F., and to break the motorcircuit when the flue gas temperature drops below a certain degree, say,for example, 200 F. The control circuit is diagrammatically illustratedin Fig. 7.

' As illustrated in Fig. 3, the foot 68 may be formed internally toprovide'a series of spiral vanes or baffles 85 which serve to impart awhirling motion to the products of combustion as they pass upwardlythrough the flue 24 and thereby expedite heat exchange with the airwhich flows through the path 26. Below the vanes 86 a draft restrictingdevice comprising a damper 88 of materially less cross sectional areathan the cross sectional area of the path 24 may be arranged, the damper88 being pivotally mounted on suitable trunnions which are .journaled inthe wall of the foot 68, and one of the trunnions may be extendedthrough the wall of the chimney Ill and provided with a handle 90 so asto permit adjustment of the damper 83 thereby to vary the efiectivedraft within the combustion chamber 28. The draft restricting device isprovided so as to restrict the effective draft within the combustionchamber 20 to that which is desirable to efficiently burn fuel thereinand so as to prevent the passage through the combustion chamber 20 andthe flue path 24 of large amounts of air which are not necessary tosupport combustion.

The air discharged 'into the upper endof the air path 26 by the blower28 flows downwardl in the unidirectional path provided between theexchanger 22 and the inside of the chimney I 0 and is discharged throughthe openings or outlets 38 formed in the chimney walls III at the lowerend of the air path 26.

The air conduit 32 for supplying air from the space I8 to be heated tothe intake side of the blower 28 comprises a T-pipe 94, a pipe 95connecting the T-pipe 94 with a header duct 98 and one or more ductssuch as I00 formed between the ceiling joists and one end of whichcommunicates with the header duct 98 and the other end of whichcommunicates with the upper end of a duct I82 formed between thestudding of the house, the lower end of the duct I02 communicating withthe air returns 36. During opertaion of the blower 28 air is withdrawnfrom the space I8 through the outlets 36, ducts I02, I00, 98 and 96, andpipe 94 and isforced by the blower 28 under pressure into the air path28 and in heat exchange relationship with the exchanger 22 and thencedischarged through the openings 38 into the space to be heated. Asillustrated in Figs. 1, 2 and 3, one of the openings 38 may communicatewith the lower end of a duct I06 which extends vertically and which isarranged along the outside of the chimney II]. The duct I86 may extendupwardly to the space between the ceiling joists and then laterally to adistant part of the house for supplying heated air thereto.

The chimney ID as illustrated in Fig. 1 is supported upon a footing IIOjust below the floor of the space I8 and at least some of the outlets 38are arranged so as to discharge heated air laterally just above thefloor of the space Hi. If desired, the chimney may be concealed byfinished walls extending therearound within the space The fuel burningmeans associated with the chamber 42 is adapted to operate independentlyof the fuel burning means associated with the chamber 44 and vice versa.In operation either or both fuel burning means are adapted to supplyheated products of combustion to the interior of the heat exchanger 22for the purpose of heating the same and When the temperature of the flue24 at the upper end of the exchanger 22 reaches a temperature of, sayfor example, 225 F., the switch 82 will close the motor circuit 80 andcause the blower 28 to circulate air to be heated through the path 25and into the space I8. The supply of fuel to the fuel burning meansassociated with both the chambers 42 and 44 is manually controlledalthough it may be auto matically controlled in accordance with thedisclosure of Patent 2,348,834 issued to me on May 16, 1944, for Heatingapparatus, and reference to which is hereby made for the details ofcontrols and other embodiments of certain particulars hereinillustrated. When the fuel supply to either or both of the fuel burningmeans associated with the chambers 42 and 44 is reduced to a point atwhich the temperature of the flue gases leaving the upper end of theheat exchanger 22 is below approximately 200 F., the switch 82 will openand discontinue operation of the blower 28.

In the event of current failure during the time that heated products ofcombustion are being supplied to the flue 24 from either or both of thefuel burning means and when the blower 28 is operating, a means fordissipating heat from the system is provided and comprises a dampercontrolled vent I I2 provided by the end of the T-pipe 84 remote fromthe blower 28 as shown in Fig. 1. A weighted damper I I4 is arranged tooccupy the 6 position illustrated in Fig. 1 when the blower 28 is atrest thereby venting the air path 26 to the attic space 34. However,when the blower 28 is operating, the suction effect of the blower 28will draw the damper I I4 to a position to close the vent I I2 andthereby will draw air from the space I8 to be heated as previouslydescribed.

The structure herein disclosed and claimed constitutes an improvementupon that disclosed in my application Serial No. 399,780, filed June 26,1941, for Heating apparatus, now Patent No. 2,274,341, issued February24, 1942, and I contemplate that the various types of heat exchangersillustrated therein may be used in the structure herein disclosed inplace of the specific type of heat exchanger herein illustrated.

In lieu of the specific types of fuel burning means illustrated herein,other types or kinds of fuel burning means may be employed, such, forexample, as those disclosed in my prior applications hereinbeforereferredto. In using the phrase different types of fuel in the claims, Imean, for example, that a hard fuel such as coal or wood is of adifferent type than a fluid fuel such as gas or a liquid fuel,

While the invention has been described with some detail, it is to beunderstood that the description is for the purpose of illustration onlyand is not definitive of the limits of the inventive idea. The right isreserved to make such changes in the details of construction andarrangement of parts as will fall within the purview of the attachedclaims.

I claim:

1. A heating system for supplying heated air to a space in a building tobe occupied by and for the comfort of human beings comprising a chimneywhich forms part of the building and which extends upright to and abovethe roof of the building and has an atmospheric discharge external ofthe space, a plurality of combustion chambers in the lower portion ofsaid chimney, means associated with each of said combustion chambers andconstructed and arranged for burning fuel and functioning to supplyheated products of combustion to said chimney, one of said means beingadapted to burn a difi'erent kind of fuel than the other, a heatexchanger member extending longitudinally of and for a substantialportion of the length of said chimney and providing a path for thefiowof the products of combustion and a separate path for flow of air inintimate heat exchange relationship with the combustion products, anoutlet from the lower end of said air path into said space, and meansincluding an air moving device operable to supply to the upper portionof said air path, air to be heated and under a pressure greater than thepressure of the products of combustion.

2. A heating system for supplying heated air to a space in a building tobe occupied by and for the comfort of human beings comprising a chimneywhich forms part of the building and which extends upright to and abovethe roof of the building and has an atmospheric discharge external ofthe space, a plurality of combustion chambers in the lower portion ofsaid chimney, means associated with each of said combustion chambers andconstructed and arranged for burning fuel and functioning to supplyheated products of combustion to said chimney, one of said means beingadapted to burn a different kind of fuel than the other, a heatexchanger member extending longitudinally of and for a substantial a;portion of the length of said chimney and providing a path for the flowof the products of combustion and a separate path for flow of air inintimate heat exchange relationship with the combustion products, anoutlet from the lower end of said air path into said space, meansincluding an air moving device operable to supply to the upper portionof said air path, air to be heated and under a pressure greater than thepressure of the products of combustion, and means for dissipating heatfrom the heat exchanger member if the air moving device fails to operatewhen at least one of said fuel burning means are generating heatedproducts of combustion.

3. A heating system for supplying heated air to a space in a building tobe occupied by and for the comfort of human beings comprising a chimneywhich forms part of the building and which extends upright to and abovethe roof of the building and has an atmospheric discharge external ofthe space, a plurality of combustion chambers in the lower portion ofsaid chimney, means associated with each of said combustion chambers andconstructed and arranged for burning fuel and functioning to supplyheated products of combustion to said chimney, one of said means beingadapted to burn a diiferent kind of fuel than the other, a heatexchanger member extending longitudinally of and for a substantialportion of the length of said chimney and providing a path for the flowof the products of combustion and a separate path for flow of air inintimate heat exchange relationship with the combustion products, anoutlet from the lower end of said air path into said space, meansincluding an air moving device operable to supply to the upper portionof said air path, air to be heated and under a pressure greater than thepressure of the products of combustion, means operable in response to anincrease in temperature in the chimney above a predetermined point foroperating said air moving device, and for discontinuing the operation ofsaid air moving device in response to a decrease in temperature in thechimney below a predetermined point, and a damper controlled vent at theupper end of said air path adapt-ed to vent said air path underpredetermined conditions, said damper controlled vent being closed bythe operation of said air moving device.

4. A heating system for supplying heated air to a space in a building tobe occupied by and for the comfort of human beings comprising a chimneywhich forms part of the building and which extends upright to and abovethe roof of the building and has an atmospheric discharge external ofthe space, a plurality of combustion chambers in the lower portion ofsaid chimney, means associated with each of said combustion chambers andconstructed and arranged for burning fuel and functioning to supplyheated products of combustion to said chimney, each of said fuel burningmeans being operable independently of or simultaneously with the other,one of said means being adapted to burn a different kind of fuel thanthe other, a heat exchanger member extending longitudinally of and for asubstantial portion of the length of said chimney and providing a pathfor flow of the products of combustion and a path for flow of air inintimate heat exchange relationship with the combustion products, anoutlet from the lower end of said air path into said space, meansincluding an air moving device operable to supply to the upper portionof said air path, air to be heated and under a pressure greater than thepressure of the products of combustion, an electrically operated sourceof power for operating said air moving device, and an electric circuittherefor including a thermostatic switch responsive to heat generated byeither or both of said fuel burning means.

5. A heating system for supplying heated air to a space in a building tobe occupied by and for the comfort of human beings comprising a chimneywhich forms a part of the building and which extends upright to andabove the roof of the building and has an atmospheric discharge externalof the space, a combustion chamber in the lower portion of said chimney,a heat exchanger member extending longitudinally of and along asubstantial portion of the length of said chimney and providing a pathfor flow of the combustion products and a separate path for flow of airin intimate heat exchange relationship with the path for flow of thecombustion products, an outlet from one end of said air path discharginginto said space, means including an air moving device operable to supplyto the other end of said air path, air to be heated and under a pressuregreater than the pressure of the products of combustion, fuel burningmeans associated with said combustion chamber and constructed andarranged for burning fuel and functioning to supply heated'products ofcombustion to said combustion products path, and other fuel burningmeans associated with said combustion chamber and constructed andarranged for burning fuel and functioning to supply heated products ofcombustion to said combustion products path, each of said fuel burningmeans being operable independently of or simultaneously with the other,

6. A heating system for supplying heated air to a space in a building tobe occupied by and for the comfort of human beings comprising a chimneywhich forms a part of the building and which extends upright to andabove the roof of the building and has an atmospheric discharge externalof the space, said chimney being constructed so as to produce a highpotential draft, a combustion chamber in the lower portion of saidchimney, fuel burning means associated with said combustion chamber andconstructed and arranged for burning fuel under natural draft operationand functioning to supply heated products of combustion to said chimney,a heat exchanger member extending longitudinally of and along asubstantial portion of the length of said chimney and providing a pathfor the flow of the products of combustion and a separate path for flowof air in intimate heat exchange relation ship with the path for flow ofthe combustion products, openings at the lower and upper ends of saidair path communicating with said space, means to supply from said spaceto one of said openings, air to be heated and under a pressure greaterthan the pressure of the products of combustion, the opening at theother end of said air path forming an outlet for discharging heated airinto said space, a draft restricting device in said chimney forrestricting the effective draft in the combustion chamber to thatrequired for efficiently burning fuel therein and which will prevent thepassage through the combustion chamber and chimney of large amounts ofair which are not necessary to support combustion, and other fuelburning means associated with said combustion chamber and operableindependent- 1y of said first-mentioned fuel burning means to supplyheated products of combustion to said chimney. a

'7. A heating system for supplying heated air to a spacein a building tobe occupied by and for the comfort of human beings comprising a chimneywhich forms a part of the buildingand which extends upright to and abovethe roof of the building and has an atmospheric discharge external ofthe space, said chimney being enlarged at its base, a combustion chamberin the enlarged portion of said chimney, a plurality of fuel burningmeans associated with said combustion chamber and constructed andarranged for burning fuel under natural draft operation and functioningto supply heated products of combustion to said chimney, a heatexchanger member extending longitudinally of and along a substantialportion of the length of said chimney and providing a path for the flowof the products of combustion and to which path the products ofcombustion from said fuel burning means are supplied at combustiontemperature and a single separate unidirectional path for flow of air inintimate heat exchange relationship with the path for flow of thecombustion products and through which path all of the air to be heatedmust pass, an outlet from the lower end of said air path discharginginto said space, means including an air moving device to supply fromsaid space to the upper end of said air path, air to be heated and undera pressure greater than the pressure of the products of combustion, eachof said fuel burning means being operable independently of the other orsimultaneously therewith without interfering with the eflicientgeneration of heated products of combustion by the other, said fuelburning means and combustion chamber being arranged at substantially thesame elevation and below the lower end of said heat exchanger member, anelectrically operated source of power for operating said air movingdevice, and an electric circuit therefor including a thermostatic switchresponsive to heat generated by either or both of said fuel burningmeans.

8. A heating system for supplying heated air to a space in a building tobe occupied by and for the comfort of human beings comprising a chimneywhich forms an integral part of the structure of the building and whichextends upright to and above the roof of the building and has anatmospheric discharge external of the space, a combustion chamber in thelower portion of said chimney, a plurality of fuel burning meansassociated with said combustion chamber and constructed and arranged forburning fuel and each of which is adapted to burn a different kind offuel and to supply heated products of combustion to said chimneyindependently of the other, a heat exchanger member extendinglongitudinally of and for a substantial portion of the length of saidchimney and providing a path for the flow of the products of combustionand a separate unidirectional path for flow of air in intimate heatexchange relationship with the combustion products, an outlet from oneend of said air path discharging into said space, means, including anair moving device, operable to supply from said space to the other endof said air path, air to be heated and under a pressure greater than thepressure of the products of combustion, a relief damper at the upper endof said air path movable to open position, upon stoppage of said airmoving device for venting said air path, an electrically operated sourceof power for operating said air moving device, and an electric circuittherefor including 10 a thermostatic switch, responsive to heat generated by either of said-fuel'burning means, said damper being closed inresponse to the operation of said air moving device; r

9. A heating system for supplying heated air to a space in a building tobe occupied by and for the comfort of human beings comprising a chimneywhich forms an integral part of the structure of the building and whichextends upright to and above the roof of the building and has anatmospheric discharge external of the space, the lower portion of saidchimney being enlarged and formed to provide a plurality of combustionchambers, each of said combustion chambers having fuel burning meansconstructed and arranged for burning fuel and functioning to supplyheated products of combustion to said chimney, each of said fuel burningmeans being independent of the other and being adapted to burn adifferent kind of fuel, a heat exchanger member extending longitudinallyof and for a substantial portion of the length of said chimney andproviding a path for the flow of the products of combustion and aseparate unidirectional path for flow of air in intimate heat exchangerelationship with the combustion products, an outlet from one end ofsaid air path discharging into said space, means, including an airmoving device, operable to supply from said space to the other end ofsaid air path, air to be heated and under a pressure greater than thepressure of the products of com bustion, and means operable in responseto an increase in temperature in the chimney above a predetermined pointfor operating said air movr ing device, and for discontinuing theoperation of said air moving device in response to a decrease intemperature in the chimney below a predetermined point.

10. A heating system for supplying heated air to a space in a buildingto be occupied by and for the comfort of human beings comprising afurnace having a plurality of fuel burning means, and means fortransferring heat generated by either or both of said fuel burning meansto air from said space to be heated comprising a common heat exchangerto which products of combustion from either or both of said fuel burningmeans are supplied, means including an air moving device for circulatingair from said space over said heat exchanger and back to said space, andmeans for dissipating heat from said heat exchanger if said air movingdevice is not operating when at least one of said fuel burning means aregenerating heated .products of combustion.

11. A heating system for supplying heated air to a space in a buildingto be occupied by and for the comfort of human beings comprising achimney which forms a partof the building and which extends upright toand above the roof of the building and has an atmospheric dischargeexternal of the space, a heat exchanger member extending longitudinallyof and along a substantial portion of the length of said chimney andproviding a path for flow of combustion products and a separate .pathfor flow of air in intimate countercurrent heat exchange relationshipwith the path for flow of combustion products, fuel burning meansoperable for burning fuel and functioning to supply heated products ofcombustion to the lower end of said combustion products path at thebottom of said heat exchanger member, other fuel burning meansconstructed and arranged for burning fuel and functioning to supplyheated products of combustion to the lower end of said combustion 12 andundera pressure greater than the pressure of theproducts of combustion,and means .0 r dissipating heat from the heat exchanger member when-saidair moving device 'is;n0t operating when at least one ofsaid fuelburning means is generating heated products of combustion. j 4

MORITZ L. MUEILER

